Speaker Wires: Can I use different Wire Gauges in the same Conductor?

I am currently experimenting with different wire materials and different wire gauges for DIY speaker cables. So far, I am getting superb mid range from two 24AWG 5N silver wires, one hot, the other for return (+). The wires are imbedded in two 22AWG PTFE tubings, meaning the actual dielectric is air. The sound is hugely dynamic and spacious! I need to open the volume control on my preamp no more than 10 O'Clock to fill the room with very loud sound. This flies in the face of everything I have heard about speaker cables in terms of wire size, 16AWG or even 12AWG being usually recommended. For my subs I use 7 parallel silver-plated copper 22AWG  each for - and +. The sound blows the roof off my place and is very physical in terms of making the skin vibrate. Now I became curious, and I do not have an answer yet: what would happen if I use different wire gauges for the hot and the return in the same cable, let's say 24AWG for the -, and 26AWG for the +? I would assume that the impedance of the entire conductor would be determined by the smallest wire (26AWG); however, since most of the energy of the hot signal is being converted into mechanical by the speaker cone, I wonder, if one could get away with having a smaller wire for the return. In the case of silver as a conductor material, this translates directly into $$$, hence my question. I could, of course, just do the experiment and listen, but I would like to understand the theory behind it, and what effect it would have on signal symmetry or "smearing".